When storing a file, a storage system may store an original file as well as a plurality of replicas of the original file in a single server or multiple distributed servers in case an error occurs. A storage system may regularly verify data consistency among an original file and its replicas. If a file is determined to be erroneous, the erroneous file may be recovered by replacing with a non-erroneous file.
However, it may be difficult for a storage systems to recover errors when errors occur in all corresponding files including an original file and all replicas using such a data consistency verification method.